Nebulizer



Aug. 12,1958 J. B. SCHMITT ETAL NEBULIZER Filed Dec. 19, 1955 lllllllIllIIIIllllllII|lllllllllllIIIIIIIIIIIHIIIIHIll! V INVENTOR. JOY B. SCHM/TT W/LL/AM H. CORBETT ATTORNEY United States Patent NEBULIZER Joy B. Schmitt and William H. Corbett, Somerset, Pa., assignors to The De Vilbiss Company, Toledo, Ohio, a corporation of Ohio This invention relates to a nebulizer for producing by atomization a fine mist or fog of aerosol particles of a size capable of being suspended in air.

Such aerosols are readily inhaled with natural respiration and are accordingly effective in administering therapeutic agents to recesses of the lungsand bronchi.

Such therapeutic agents include antibiotics, epinephrines and detergents, the latter serving to relieve congestion by reducing the viscosity of substances clogging or irritating the respiratory tract.

In order that the medicinal substances effectively react and are deposited upon the areas being treated the aerosols in which they are carried must be composed of particles which are neither large enough to collect in the mouth, throat or nasal passageways nor so small as to be air borne in and out of the lungs.

The deposit of large drops of a medicament mayhave a deleterious effect upon the contacted tissues and not only wastes the material but also makes uncertain the quantity that is actually efiective. Accurate control of the treatment is thereby lost. The latter objectionable features also attend the application of too fine a mist which is largely lost with the exhaled air.

Accordingly it is most important that the nebulizing instrument for use in applying such aerosols be designed to produce particles predominantly in the efiective size range with a minimum number of a size above and below the range. I

A prime object of this invention is to provide a nebulizer that forms an aerosol of uniform and stable particle size.

Another important object is the provision of a nebulizer that is capable of producing an aerosol of the desired characteristics in high and continuous volume.

Another object of the invention is to provide such an instrument with means for governing the rate of discharge.

A further object is the provision of a nebulizer which may easily be arranged to discharge in any direction desired, independent of the location of the tubing or hose supplying atomizing air.

Another object is the provision of a nebulizer that is inexpensive to produce, easy to clean, and of simple design.

Other objects and advantages of the invention will become apparent upon reading the following description and referring to the drawings, in which:

Figure 1 is a vertical section of a nebulizer embodying the invention;

Figure 2 is a horizontal section taken on the line 2-2 of Figure 1;

Figure 3 is' an elevation partly in vertical section of the spray nozzle;

Figure 4 is a vertical section showing the mounting of the spray nozzle taken on the line 4-4 of Figure 1; and

Figure 5 is an elevation of the air vent adjusting cap.

Referring to the drawings in more detail the nebulizer embodying the invention has a cylindrical shell 1 with an 2 integral flange 2 at its lower end; A retaining ring 3 hanging loosely from the flange has threads by which a receptacle 4 for the liquid to be nebulized is fastened to the shell with an intervening sealing gasket.

Within and concentric with the shell is a cylindrical tube 5. The tube has a surrounding band 6 by which it is rotatably mounted within the socket 7 formed in the annular shell closure 8. The latter is brazed to the upper end of the shell.

Inserted into the upper end of the tube 5 is an air vent adjusting cap 9. It is frictionally held in place by the outward spring of arms 10 and 11 below opening 13 as shown in Figure 5. In this view the opening 13 is illustrated as having less than its true width in order to show the edges of the adjoining lined sides of the cap.

A small lip 12 turned inwardly from the upper edge of tube 5 projects into the opening 13 above the arms 10 and 11 and prevents accidental withdrawal of the cap 9 by meeting the edge of one of the arms. The cap of course may be removed by lining up the lip with the vertical slot between the ends of the arms.

An atomizing nozzle 14 projects into tube 5 through a mounting nipple 15 fixed in the wall of the tube. A fiat on the upper side of the flange 16 on the outer end of the nozzle fits below the fiat bottomed projection 17 on the nipple 15 to position the nozzle with its discharge port 18 directed downwardly and approximately axially of the tube 5.

Air is delivered to the atomizing nozzle through the hose receiving stem 19 held against the nozzle by the nut 20. The medicated liquid reaches the nozzle from the receptacle 14 through plastic tubing 21 inserted into the inner end of the nozzle.

Air passage 22 within the nozzle connects to a vertical bore 23 terminating in the discharge port 18 in aspirating relation to the inclined liquid channel 24.

Projecting laterally from the shell 1 is the aerosol outlet spout 25.

In the operation of this nebulizer the receptacle is first filled about three-fourths full with the selected medicated liquid whereby the level of the liquid is moderately spaced below the bottom of the tube 5. A source of compressed air or oxygen regulated to a pressure from 6 to 15 pounds (p. s. i.) is connected by hose to the hose receiving stem 19. The position selected for the spout 25 is independent of the direction from which an air supply hose may come from a compressor or tank as the cylindrical tube 5 is freely rotatable within socket 7. The patient receiving the treatment may be in a bed within an open topped enclosure for a long period of inhalation should a detergent solution be involved for relieving asthma or other semi-chronic respiratory ailments.

In case of an antibiotic or epinephrine application the treatment may be of short duration with inhalation directly from the outlet spout 25.

From the discharge port 18 of the nozzle 14 a conical spray of the atomized medicated liquid is projected downwardly within the tube 5. The interior of the tube is wetted by the spray and heavier particles of the spray mass hitting the wetted surface are adsorbed and hence removed from the body of the spray.

Additional heavy particles in the atomized stream are eliminated on leaving the tube by being impelled by their weight to penetrate the surface of the liquid in the receptacle. Thus the character of the spray particles is further refined.

The air borne nature of the remaining spray particles permit them to turn upwardly with the air into shell 1 and subsequently from outlet spout 25. The outer surface of the tube 5 and the inner surface of the shell 1 as well as the inwardly projecting portion of the outlet 3 spout provide additional contact surface for continued precipitation of the coarser parts of the atomized stream.

Consequently the mist emitted from the outlet spout is in a substantially pureaerosol form composed of particles of a very uniform and diminutive size.

The volume of the aerosol mist may be varied by vertical adjustment of the cap 9. The minimum, approximately 300 cc., of the liquid is nebulized in a twenty-four hour period with the cap pushed down to closed position in which the air entering opening 13 is completely sealed by tube 5. The maximum rate of 1900 cc. in a twenty-four hour period is secured by raising the regulator cap to full open position with the top edge of one of the arms 10. and 11 against the stopping lip 12. If a certain delivery rate somewhere between the minimum and maximum is desired it may be approximated by opening the regulator cap a proportional amount. The equally spaced grooved rings around the cap provide reference lines for measuring the degree of opening and also may be used for identifying a previously used intermediate setting.

The extra air drawn through the regulator cap increases the capacity of the nebulizer by adding to the volume and velocity of the air carrying the atomized particles.

In order that such an instrument be maintained in good working order and in a sterile condition it should be frequently cleaned thoroughly with water or alcohol. The design of this nebulizer is particularly well adapted for rapidly and efficiently accomplishing this purpose. By removing nut 20 the spray nozzle 14 with attached tubing 21 may be withdrawn through the mounting nipple 15. Tube 5 is easily raised out of shell 1. With removal of the cap 9 and the receptacle all parts are readily washed and dried. The nozzle ports may require the insertion of a fine wire.

The ease of disassembly is derived from the simple design which also contributes to the low cost of manufacturing this improved instrument.

From the preceding description it may be seen that the objects of the invention are well attained by the embodiment here presented.

Various modifications within the scope of the invention and of the appended claims will be apparent to those skilled in the art.

What we claim is:

1. A nebulizer having a vertically positioned cylindrical shell, a receptacle for the liquid to be nebulized, a retainer holding the receptacle to the shell, a cylindrical tube smaller in diameter than the shell mounted concentrically within the shell, a laterally directed outlet from the shell, an atomizing nozzle inside of the tube facing downwardly toward the open lower end of the tube and the surface of the liquid within the receptacle, said nozzle being formed of a horizontally-positioned, single piece of tubular stock with an axial bore at one end for the entry of air and an axial bore at the other end for the entry of liquid, said bores terminating short of each other, and said tubular stock having a discharge opening in its lower side to which lateral passages from the inner ends of the two axial bores communicate, a tubing delivering liquid from the receptacle to the nozzle, and a connection for conveying atomizing air to the nozzle, the various elements being so designed and arranged that the spray discharged from the nozzle travels down the tube into the receptacle and upwardly therefrom into the shell and through the laterally directed outlet, with the larger particles removed from the spray by impingement against the surfaces of the tube, the shell and the liquid in the receptacle.

2. A nebulizer having a vertically positioned cylindrical outer shell, a flat cap on the upper end of the shell, a receptacle for the liquid to be nebulized, a retainer holding the receptacle to the lower open end of the shell, a cylindrical tube, smaller in diameter than the shell, mounted axially within the shell and extending upwardly through and substantially above the fiat cap on the upper end of the shell, an atomizing nozzle inside of the tube at a point above the upper end of the shell, said atomizing nozzle discharging downwardly through the open lower end of the tube and toward the surface of the liquid in the receptacle, a tubing delivering liquid from the receptacle to the nozzle, a connection in the upper exposed end of the cylindrical tube for conveying atomizing air to the nozzle, and a laterally directed spray outlet from the shell.

3. A-nebulizer according to claim 2 in which there is an adjustable cap on the upper end of the tube for permitting a variable amount of atmospheric air to be drawn into the tube under the aspirating effect of the atomizing nozzle.

4. A nebulizer according to claim 2 in which the tube is rotatably mounted in the flat cap of the shell whereby the tube may be rotated to receive air from any direction without disturbing the selected position of the laterally directed outlet from the shell.

5. A nebulizer according to claim 2 in which the atomizing nozzle is tubular in form and disposed in a horizontal position with the liquid tubing connected to one end and the air connection in communication with the other end.

6. A nebulizer according to claim 2 in which the atomizing nozzle is removably mounted through an opening in the side of the cylindrical tube and the liquid delivering tubing is resilient whereby the nozzle and the attached tubing may be withdrawn together through the opening for cleaning purposes, and there are means establishing the proper position of the nozzle when it is reinserted through the opening.

References Cited in the file of this patent UNITED STATES PATENTS 2,577,550 Wahlin Dec. 4, 1951 FOREIGN PATENTS 569,753 Great Britain Aug. 24, 1944 

